The Firebird 2.1.1 packages are now in ppa for Ubuntu Dapper, Gutsy , Feisty , Hardy and Intrepid Ibex
The guide for installing is located in the ubuntu wiki
[Update:Intrepid/Dapper builds are added and is now officially released ]
This document describes how to install a mail server based on Postfix that is based on virtual users and domains, i.e. users and domains that are in a MySQL database<sep/>